Table 1.

Summary statistics for binary classification by Random Forest (RF) of first morning void spot urine samples stored under different conditions within preservative-coated and non-coated vacuum tubes

Pairwise	Preservative-coated tube			Non-coated tube
	Classification accuracy	AUC	RF classification margin	Classification accuracy	AUC	RF classification margin
Control v. 2 d at 4°C	0·30	0·24	–0·11	0·23	0·16	–0·16
Control v. 7 d at 4°C	0·26	0·20	–0·13	0·20	0·15	–0·18
Control v. 2 d at RT	0·30	0·26	–0·12	0·21	0·16	–0·16
Control v. 7 d at RT	0·31	0·25	–0·10	0·27	0·20	–0·14
2 d at 4°C v. 7 d at 4°C	0·29	0·25	–0·11	0·20	0·13	–0·19
2 d at 4°C v. 2 d at RT	0·31	0·28	–0·11	0·24	0·16	–0·16
2 d at 4°C v. 7 d at RT	0·30	0·24	–0·12	0·27	0·20	–0·14
7 d at RT v. 2 d at RT	0·27	0·19	–0·15	0·25	0·18	–0·15
7 d at 4°C v. 7 d at RT	0·29	0·23	–0·12	0·25	0·19	–0·14
2 d at RT v. 7 d at RT	0·28	0·23	–0·12	0·22	0·16	–0·16

Control, storage at –20°C; RT, room temperature; AUC, area under the receiver operating characteristic curve.